or maybe this: https://itunes.apple.com/us/app/lepsi-watch-magnetism/id1080183882?mt=8
Thanks. Used both. Turns out it's magnetised enough to turn a CRT funny colours.
@pdlouche started
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or maybe this:
https://itunes.apple.com/us/app/lepsi-watch-magnetism/id1080183882?mt=8